Search Results (863)

Grazing systems, commonly considered less productive than indoor livestock farming, account for most farms and agricultural land worldwide. Beyond feeding livestock, they fulfil essential environmental, economic, and social functions that are particularly relevant to sustainable development in the context of climate change, resource constraints, and population growth. By relying on circular resource use and promoting ecological processes, grazing systems can offset methane emissions from livestock through soil carbon sequestration while preserving biodiversity, maintaining landscapes, and reducing fire risks. In order to assess whether grazing systems are actually less productive than indoor systems, data from comparative trials assessing these two feeding environments published over 40 years were used as the basis for a meta-analysis published in 2014. This analysis showed that animal performance on pasture was equivalent to that indoors, despite the supplementation provided primarily to indoor feeding environments. Given the economic and environmental context and the challenges related to the sustainable development of livestock farming, here, we present this 2014 data to encourage its equitable reuse and contribute to a better overall assessment of grazing in current debates, considering all aspects, including animal performance. Furthermore, supplementing this initial dataset with additional data will lead to an even more comprehensive evaluation of these grass-based livestock systems. Full article

Nitrogen fertilization is widely recognized as a key factor influencing tropical grass productivity; however, its effectiveness may vary according to pasture developmental stage and management practices. This study evaluated the effects of five nitrogen rates (0, 75, 150, 225, and 300 kg ha⁻¹) and two post-cutting residual heights (20 and 30 cm) on the productive, morphological, and nutritional characteristics of Aruana grass (Megathyrsus maximus cv. Aruana) under irrigated conditions. Treatments were arranged in a randomized complete block design with a split-plot structure. Nitrogen was applied as urea in three split applications following simulated grazing events. Herbage mass, dry matter yield, morphological composition, chemical composition, and in vitro dry matter digestibility were evaluated. No interaction was detected between nitrogen fertilization and residual height. Nitrogen fertilization did not affect forage production, morphological composition, chemical composition, or digestibility under the conditions of this study. Residual height influenced forage accumulation, with greater herbage mass and dry matter yield observed at 20 cm than at 30 cm (p = 0.006), without affecting forage quality. These preliminary findings indicate that residual height may be an important factor affecting forage accumulation in irrigated Aruana grass during pasture establishment. Additional studies conducted over multiple growing seasons and environmental conditions are required before definitive management recommendations can be made. Full article

For soil processes that are known to be temporally dynamic, such as soil respiration, methanogenesis, and nitrification–denitrification, it is challenging to capture temporal variations with field-portable greenhouse gas (GHG) analyzers to provide the most accurate estimates of season-long GHG emissions and global warming potentials (GWPs). The objective of this field study was to evaluate the effects of measurement frequency (i.e., weekly, every other week, and every third week), replication (i.e., three, four, or five), and their interaction on the consistency of season-long carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) emissions and GWP estimates across multiple ecosystems. Results are based on direct, in-field measurements with a field-portable gas analyzer. Field research was conducted throughout the 2024 growing season in a minimally grazed pasture, tallgrass prairie, soybean under conventional and conservation management practices, and cotton under conservation management in Arkansas, USA. Season-long CO₂ emissions and GWP from the tallgrass prairie were 1.1 times (12%) greater from the weekly and every-other-week (16.9 and 17.0 Mg ha⁻¹, respectively), which did not differ, than the every-third-week (14.2 and 14.2 Mg ha⁻¹, respectively) measurement frequencies. Season-long CH₄ emissions from the minimally grazed pasture and conservation-tilled soybean system were ≥7.5 times greater with four and five replications, which did not differ, than with three replications. Global warming potential in the conservation-tilled soybean (13.9 Mg ha⁻¹) and conservation-tilled cotton (21.1 Mg ha⁻¹) systems were ≥1.1 times (13%) greater with the every-third-week than with the weekly data set. Though this study was somewhat limited due the data sub-setting approach used, even using current, state-of-the-art, field-portable GHG analyzers, an appropriate in-field measurement frequency and number of spatial replications should be considered to reliably quantify whole-field, season-long GHG emissions and GWP estimates. Full article

Virtual fencing is increasingly used in grazing systems as a flexible alternative to physical fencing, yet detailed assessments of cattle behavior within such systems remain limited. This study investigates the use of collar-mounted tri-axial accelerometers combined with supervised machine learning to characterize cattle behavior in a virtual fencing system. Seven free-ranging Angus cattle were monitored using accelerometers mounted on a virtual fencing system, GNSS positioning, and virtual fence warning logs. A random forest classifier was developed and trained to identify key behaviors (grazing/feeding, ruminating, lying, standing and locomotion) using features derived from tri-axial accelerometer data. The model achieved high classification performance for grazing/feeding, ruminating, and lying (mean accuracy = 0.87, range = 0.83–0.90), enabling estimation of individual behavioral time budgets. Daily activity patterns were generally stable over time and across individuals. Spatial analyses revealed significant differences in behavior between areas near the virtual fence boundary and interior pasture locations, with increased grazing and reduced ruminating near the boundary, potentially reflecting spatial variation in habitat type or forage availability. In the virtual fencing system, cattle are equipped with collars that emit an auditory warning when they approach a virtual boundary, followed by a low-energy electrical impulse when the warning is ignored over a directional distance of 5–10 m. Event-based analyses showed no consistent short-term changes in either movement intensity and direction nor locomotion following auditory warning events, indicating that cattle habituated to the system did not exhibit uniform behavioral disturbance in response to warnings. These results suggest that accelerometer-based behavior classification can provide fine-scale, non-invasive insights into spatio-temporal cattle behavior in virtual fencing systems. The finding indicates that, in a habituated herd, virtual fencing was not associated with pronounced disruption to the measured behavioral patterns, while highlighting the potential of embedded sensor data for animal-based behavioral monitoring. Full article

Pasture ecosystems are a key component of livestock production in arid and semi-arid regions, where forage availability and nutritive value are often associated with animal performance under grazing conditions. This study aimed to provide an exploratory assessment of pasture productivity, forage nutritive value, and beef cattle productivity across contrasting natural–climatic settings in Kazakhstan. The study was conducted under commercial production conditions on five farms representing different grazing environments during the 2024–2025 grazing seasons. Because each zone was represented by a single farm, the study should be interpreted as an observational assessment of farm-level patterns rather than as a fully replicated experimental comparison. Pasture productivity and forage chemical composition, including crude protein, fiber, and dry matter content, varied among farms and seasons. Average daily gain ranged from 316.7 to 900 g day⁻¹ depending on the study site and year of observation. Exploratory statistical analyses indicated variability among the studied systems; however, pairwise comparisons did not reveal statistically significant differences in animal productivity among farms (p > 0.05). Correlation analyses revealed moderate positive associations between average daily gain, crude protein content, and pasture yield, although these relationships were not statistically significant after adjustment for multiple comparisons. Similarly, linear models incorporating forage nutritive value indicators and study site did not identify statistically significant predictors of animal productivity within the current dataset. Overall, the results describe patterns of variation in pasture characteristics and animal productivity observed under extensive grazing conditions in continental environments. Given the observational design and limited replication at the farm level, the findings should be interpreted cautiously and regarded as preliminary. The study provides baseline information for future investigations of pasture–livestock interactions in arid and semi-arid grazing environments. Full article

This study addresses the issue of accurate and rapid aboveground biomass estimation in rangeland ecosystems, as traditional grazing methods are labor-intensive, while modern remote sensing techniques often require expensive equipment and controlled conditions. The goal of this work is to develop an efficient and accessible approach for biomass estimation of natural pastures based on ground-level RGB images captured with smartphones. For this purpose, a dataset consisting of 1196 field images and corresponding biomass values collected from 40 districts in southern Kazakhstan was used, and a wide + tiles architecture based on the DINOv3 model of Vision Transformer was proposed. The model utilized attention pooling and feature fusion mechanisms to integrate both global and local features, and various preprocessing and augmentation strategies were comparatively examined. Experimental results demonstrated that the proposed method exhibits high accuracy (with the best result being R² = 0.733, MAE ≈ 0.779 c/ha), where the DINOv3 model showed clear advantages over ConvNeXtV2. Furthermore, the impact of preprocessing strategies was minimal, and the importance of high-resolution images was clearly established. The obtained results show that the proposed method performs consistently under heterogeneous field conditions and allows for reliable biomass estimation without the need for specialized equipment. This makes it a practical tool for monitoring pastures, planning forage supply, and supporting agronomic decision-making. Full article

This study evaluated the effects of replacing alfalfa hay with sulla [Sulla coronaria (L.) B.H. Choi & H. Ohashi] hay or sulla haylage in pasture-based diets for lactating Sarda ewes on milk production, milk composition, and nutrient utilization efficiency. Seventy-two mid-lactation ewes were assigned to three dietary treatments for 56 days—alfalfa hay (AH), sulla hay (SH), or sulla haylage (SHL)—all combined with 3 h/day grazing and a fixed amount of supplemental concentrate. The diets were formulated to be theoretically isoenergetic and isoproteic. Pasture nutritive value was generally comparable among the groups throughout the experimental period. Milk yield did not differ among treatments; however, fat- and protein-corrected milk (FPCM) and milk fat and protein concentrations were higher in AH compared with the sulla-based diets. Actual nutrient intake differed among treatments, with nitrogen intake (NI) being greatest in AH, consistent with the higher milk urea concentration observed in this group. Estimated apparent energy utilization efficiency (FPCM/UFL intake) showed treatment-associated differences in exploratory analyses, with lower values observed in SH compared with AH and SHL. Similarly, exploratory estimates of apparent nitrogen utilization efficiency (Milk N/NI) were highest in SHL, intermediate in SH, and lowest in AH (p < 0.001). Condensed tannins were not detected in the conserved sulla forages under the analytical conditions adopted in this study. Therefore, the observed responses were unlikely to be directly associated with detectable condensed tannin activity. Overall, the results suggest that forage conservation method may influence milk composition and estimated apparent nutrient utilization indices, with sulla haylage showing higher exploratory estimates of apparent nitrogen utilization efficiency without negative effects on milk yield under the conditions of the present study. Full article

Grazing lands are foundational for the United States (US) livestock industry. In Arkansas, pastures are essential for rotational grazing and dairy operations. Climate change is an increasing concern in agriculture due to anthropogenic activities promoting greenhouse gas (GHG) emissions, partly due to nutrient recycling that occurs from animal manure additions. The objective of this study was to quantify and evaluate the potential effects of grazing method (i.e., enhanced grazed (EG) and minimally grazed (MG))on carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) fluxes, season-long emissions, and global warming potential (GWP) over two consecutive growing seasons (i.e., 2024 and 2025) in the Ozark Highlands region of northwest Arkansas. In 2024, averaged over time, the CO₂ flux from the EG (880 mg m⁻² h⁻¹) was greater (p ≤ 0.05) than from the MG (687 mg m⁻² h⁻¹) treatment. Averaged across grazing treatment, season-long CO₂ emissions and GWP were at least 1.8 times greater (p ≤ 0.05) in 2025 than 2024, while season-long CH₄ emissions were 4.6 times greater (p ≤ 0.05) in 2024 than 2025. Averaged across year, season-long N₂O emissions were greater (p ≤ 0.05) from the EG (1.6 kg ha⁻¹) than from the MG (0.38 kg ha⁻¹) treatment. Two-year-cumulative, season-long CH₄ and N₂O emissions and GWP from only CH₄ and N₂O were greater (p ≤ 0.05) in the EG compared to the MG treatment. Considering the large land area devoted to various agricultural grazing operations throughout the US, understanding the magnitude of GHG emissions from different grazing strategies will contribute to improving GHG mitigation efforts in managed grazing lands. Full article

Alpine shrub meadows on the Qinghai–Tibet Plateau are key warm-season pastures that support pastoral production and ecosystem stability in fragile high-elevation regions. Due to low temperatures, short growing seasons, and slow vegetation recovery, these pastures are highly sensitive to inappropriate grazing management. However, the effects of different grazing–rest time configurations on plant community composition and leaf functional traits in alpine shrub meadows remain insufficiently understood. In this study, we evaluated five grazing treatments in an alpine shrub meadow in Sunan County, central–eastern Qilian Mountains: 10 days grazing–20 days rest (T1), 15 days grazing–15 days rest (T2), 20 days grazing–10 days rest (T3), continuous grazing (CG), and grazing exclusion (CK). In the third year of treatment implementation, we measured the community diversity, species importance values, and leaf functional traits of four dominant species: Elymus nutans, Carex tibetikobresia, Oxytropis kansuensis, and Bistorta vivipara. T1 and T2 significantly increased species richness, Shannon–Wiener diversity, and Simpson diversity compared with CG and CK. NMDS and PERMANOVA further showed significant differences in overall community composition among grazing treatments. Grazing generally reduced the leaf length, leaf width, and leaf area, whereas T2 showed relatively stronger leaf recovery among grazing treatments. Specific leaf area, specific leaf weight, and leaf length–width ratio showed higher variability and calculated plasticity than leaf thickness and leaf dry matter content, suggesting that resource-acquisition and morphological traits were more responsive to grazing than conservative structural traits. The coefficient of variation of leaf traits was positively associated with the plasticity index, although this association should be interpreted cautiously because both indices were calculated from the same underlying trait dataset. Overall, under the conditions of this three-year, single-site experiment and a target moderate grazing intensity, the 15-day grazing–15-day rest regime performed best among the tested treatments. This regime may provide a practical reference for rotational grazing management in similar warm-season alpine shrub meadows, but its broader applicability requires further validation across different grassland types, grazing intensities, climatic conditions, and longer monitoring periods. Full article

Mare milk is rich in nutrients and bioactive compounds, and its composition changes throughout lactation. This study investigated variations in the production, nutritional composition, and bioactive components of Yili mare milk across lactation stages. Twenty-six healthy grazing Yili mares were sampled on days 1, 10, 30, 60, 90, and 120 of lactation. Milk production, nutritional components, amino acids, fatty acids, minerals, vitamins, and immunologically active proteins were analyzed. Milk production peaked on day 30 and then declined. Colostrum contained significantly higher fat, protein, solids-not-fat, total solids, minerals, lactoferrin, lysozyme, and immunoglobulins than mature milk (p < 0.05), whereas lactose increased and stabilized after day 30. Essential amino acids peaked on day 30. As lactation progressed, saturated fatty acids decreased while polyunsaturated fatty acids increased. Vitamin profiles also varied across lactation, with ascorbic acid increasing during late lactation. β-casein content was higher during mid-lactation. In summary, colostrum is enriched in immunoactive proteins and minerals, whereas mature milk exhibits a more balanced amino acid and fatty acid profile. While these observed variations likely reflect the combined effect of lactation stage and seasonal pasture fluctuations under natural grazing, these findings provide practical insights into changes in milk composition in grazing Yili mares and may support the development of mare milk products under similar grazing systems. Full article

Seasonal variability in feed availability in Mediterranean dairy sheep systems can compromise animal performance and welfare, highlighting the need for reliable, high-frequency monitoring tools. Live weight (LW) is a key indicator of nutritional status, but conventional measurements are labour-intensive and poorly suited to dynamic conditions. Walk-over-weighing (WoW) systems integrated with electronic identification (EID) enable automated, continuous, individual-level LW monitoring. This study assessed the sensitivity of a WoW system to detect nutritionally driven LW changes in Sarda dairy ewes under indoor and grazing conditions. Two experiments were conducted: an indoor short-term nutritional challenge involving 24 non-lactating ewes and a grazing trial with contrasting pasture access times involving 48 lactating ewes. In both experiments, the WoW system detected consistent LW differences between nutritional treatments (p < 0.001), capturing both short-term responses and sustained LW dynamics. Differences were approximately 5%, indicating that the WoW system was sensitive to nutritionally induced LW variation under the experimental conditions of the present study, before marked changes in body condition score (BCS) became detectable. These results demonstrate that WoW systems can reliably capture LW trajectories in response to nutritional variation. However, LW responses should be interpreted cautiously, as short-term variation may also reflect gut fill and hydration dynamics, and intake information was not fully available at the individual level because some feed intake components were measured at the group level or estimated indirectly. Integrating automated LW data with production and management information may support group-level nutritional decisions and early detection of animals deviating from expected LW trajectories in precision dairy sheep systems. Full article

Efficient grazing management is critical for optimising animal growth and carcass quality in dairy beef systems; however, the combined effects of turnout date to spring pasture and post-grazing sward height have not been well quantified. This study evaluated the effects of spring turnout date (early vs. late) and post-grazing sward height (3.5 vs. 5.5 cm) on steer performance, intake, and carcass attributes, over three production cycles in a dairy calf-to-beef system. A total of 188 dairy and dairy × beef steers (initial body weight approximately 250–285 kg) were used across three experiments, conducted in a pasture-based calf-to-beef system. Animals grazed for ~200 days followed by ~100 days of indoor finishing. Early turnout improved average daily gain during early- and mid-season (p < 0.05 to p < 0.001), but differences had disappeared by housing, with no effect on carcass traits (p > 0.05). Grazing swards to 5.5 cm increased average daily gain at pasture (p < 0.01) and housing weight in the three experiments (p < 0.01). Animals grazed to 3.5 cm at pasture subsequently had a higher indoor finishing average daily gain (p < 0.05). Grazing to a stubble height of 5.5 cm improved (p < 0.001) daily gain at pasture but reduced finishing daily gain (p < 0.001). Carcass weight per day of age and were unaffected by either factor (p > 0.05), and no significant turnout × post-grazing sward height interactions were detected for any measured variables (p > 0.05). These findings indicate that maintaining a higher post-grazing sward height provides improved animal performance, while early turnout offers short-term gains, supporting grazing strategies that prioritise sward height management for sustained performance. Full article

The risk of subacute ruminal acidosis (SARA) in grazing dairy cows remains uncertain, particularly when concentrates are supplemented. This study evaluated the effects of concentrate supplementation on the evolution of diurnal ruminal pH and its relationship with production, nutrient utilization, digestive indicators, and health status. Eight ruminal-fistulated multiparous Holstein–Friesian cows were assigned to a 2-period crossover design comparing a pasture-only diet (PO) and the same pasture supplemented with 6 kg/d of grain-based concentrate (PC). Each 28 d period included 21 d of adaptation and 7 d of measurements. Cows were fed freshly cut perennial ryegrass. Ruminal pH was recorded at 0, 2, 4, 6, 8, 10, 12, and 18 h relative to feeding. Concentrate supplementation slightly decreased minimum ruminal pH (5.97 vs. 6.15) but remained above the SARA threshold. Total volatile fatty acids (VFAs) increased, and acetate molar percentage decreased with supplementation. Total dry matter intake increased by 3.5 kg/d, increasing milk yield by 3.85 kg/d, and improving milk protein concentration, while milk fat and fatty acid profile, ruminal ammonium, and clinical indicators were unaffected. Ruminal pH was higher and VFA concentrations lower late in the season. Overall, concentrate supplementation was associated with improved productivity without compromising ruminal stability under the conditions of this study; however, responses were influenced by seasonal variation in pasture characteristics. Full article

Background/Objectives: Seasonal crude protein (CP) and phosphorus (P) deficiency in northern Australian pastures reduces feed intake and growth of grazing ruminants, but the hepatic mitochondrial mechanisms underlying this response remain unclear. We characterized the hepatic mitochondrial transcriptome of sheep exposed to CP-P deficiency or matched-intake feed restriction. Methods: Merino wethers were assigned for 63 d to one of three treatments (n = 8/group): High CP-P, Low CP-P, or Restricted, in which High CP-P feed was offered at the same energy intake as the Low CP-P group. Liver RNA was sequenced, and transcripts encoding mitochondrial proteins were identified using MitoCarta 3.0. Differentially expressed genes (DEGs) were defined as adjusted p < 0.05 and |log2FC| ≥ 0.585. Results: Of 804 mitochondrial genes detected, 83 were differentially expressed in at least one pairwise comparison. The greatest transcriptional response occurred in contrasts against High CP-P (Low CP-P vs. High CP-P: 38 DEGs in 8 enriched pathways; Restricted vs. High CP-P: 37 DEGs in 10 enriched pathways). In both low-intake treatments, ALDH1L2, ALDH1L1, SHMT2, and DMGDH were upregulated, suggesting altered folate-mediated one-carbon metabolism. Restricted sheep also showed higher expression of several SLC25A transporters (SLC25A4, SLC25A28, SLC25A29, SLC25A33, and SLC25A34), indicative of enhanced mitochondrial nucleotide and metabolite exchange under CP-P adequate energy restriction. In contrast, Low CP-P sheep showed higher expression of SLC25A15 and SLC25A25 relative to either High CP-P or Restricted sheep, a nutrient-deficiency specific transporter response. CKMT2 expression was also higher in Restricted sheep than in both other groups. Conclusions: These findings suggest that reduced metabolizable energy intake was associated with the bulk of the hepatic mitochondrial transcriptional response, particularly in folate-mediated one-carbon metabolism, whereas CP-P deficiency was associated with a smaller but distinct transporter signature. The liver mitochondrial transcriptome may provide mechanistic insight into nutritional adaptation under CP and P deficiency in grazing sheep. Full article

Spatial and temporal heterogeneity in pasture quantity and nutritive value remains a major constraint to efficient nutritional management in grazing-ruminant systems. This critical narrative review was based on targeted searches of peer-reviewed literature on pasture heterogeneity, forage quality assessment, grazing management, animal monitoring, and data integration in grazing-ruminant systems, with emphasis on both recent studies and conceptually foundational work. Precision technologies have emerged as complementary tools that can improve the characterization of pasture resources, animal responses, and grazing dynamics, but their value depends on whether they support nutritionally relevant decisions under field conditions. This review examines current precision approaches, such as portable near-infrared spectroscopy, proximal and remote sensing, geospatial tools, animal-mounted sensors, and grazing-control technologies, and their capacity to improve decisions related to supplementation, stocking rate, grazing rotation, and pasture allocation. Across technologies, performance and applicability vary substantially with observational scale, calibration requirements, and validation context. This review also highlights persistent constraints, including calibration robustness, transferability across systems, field validation, interoperability, economic feasibility, and barriers to routine adoption. Precision tools can improve pasture-based nutritional management, but their practical contribution depends on how effectively they are validated, integrated, and translated into decision-support logic under commercial grazing conditions. Full article